/* eslint-disable no-redeclare */

/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/

/**
 * @returns whether the provided parameter is a JavaScript String or not.
 */
export function isString(str: unknown): str is string {
  return typeof str === 'string';
}

/**
 * @returns whether the provided parameter is a JavaScript Array and each element in the array is a string.
 */
export function isStringArray(value: unknown): value is string[] {
  return Array.isArray(value) && (<unknown[]>value).every((elem) => isString(elem));
}

/**
 * @returns whether the provided parameter is of type `object` but **not**
 *	`null`, an `array`, a `regexp`, nor a `date`.
 */
export function isObject(obj: unknown): obj is Object {
  // The method can't do a type cast since there are type (like strings) which
  // are subclasses of any put not positvely matched by the function. Hence type
  // narrowing results in wrong results.
  return (
    typeof obj === 'object' &&
    obj !== null &&
    !Array.isArray(obj) &&
    !(obj instanceof RegExp) &&
    !(obj instanceof Date)
  );
}

/**
 * @returns whether the provided parameter is of type `Buffer` or Uint8Array dervived type
 */
export function isTypedArray(obj: unknown): obj is Object {
  const TypedArray = Object.getPrototypeOf(Uint8Array);
  return typeof obj === 'object' && obj instanceof TypedArray;
}

/**
 * In **contrast** to just checking `typeof` this will return `false` for `NaN`.
 * @returns whether the provided parameter is a JavaScript Number or not.
 */
export function isNumber(obj: unknown): obj is number {
  return typeof obj === 'number' && !isNaN(obj);
}

/**
 * @returns whether the provided parameter is an Iterable, casting to the given generic
 */
export function isIterable<T>(obj: unknown): obj is Iterable<T> {
  return !!obj && typeof (obj as any)[Symbol.iterator] === 'function';
}

/**
 * @returns whether the provided parameter is a JavaScript Boolean or not.
 */
export function isBoolean(obj: unknown): obj is boolean {
  return obj === true || obj === false;
}

/**
 * @returns whether the provided parameter is undefined.
 */
export function isUndefined(obj: unknown): obj is undefined {
  return typeof obj === 'undefined';
}

/**
 * @returns whether the provided parameter is defined.
 */
export function isDefined<T>(arg: T | null | undefined): arg is T {
  return !isUndefinedOrNull(arg);
}

/**
 * @returns whether the provided parameter is undefined or null.
 */
export function isUndefinedOrNull(obj: unknown): obj is undefined | null {
  return isUndefined(obj) || obj === null;
}

export function assertType(condition: unknown, type?: string): asserts condition {
  if (!condition) {
    throw new Error(type ? `Unexpected type, expected '${type}'` : 'Unexpected type');
  }
}

/**
 * Asserts that the argument passed in is neither undefined nor null.
 */
export function assertIsDefined<T>(arg: T | null | undefined): T {
  if (isUndefinedOrNull(arg)) {
    throw new Error('Assertion Failed: argument is undefined or null');
  }

  return arg;
}

/**
 * Asserts that each argument passed in is neither undefined nor null.
 */
export function assertAllDefined<T1, T2>(
  t1: T1 | null | undefined,
  t2: T2 | null | undefined,
): [T1, T2];
export function assertAllDefined<T1, T2, T3>(
  t1: T1 | null | undefined,
  t2: T2 | null | undefined,
  t3: T3 | null | undefined,
): [T1, T2, T3];
export function assertAllDefined<T1, T2, T3, T4>(
  t1: T1 | null | undefined,
  t2: T2 | null | undefined,
  t3: T3 | null | undefined,
  t4: T4 | null | undefined,
): [T1, T2, T3, T4];
export function assertAllDefined(...args: (unknown | null | undefined)[]): unknown[] {
  const result: any[] = [];

  for (let i = 0; i < args.length; i++) {
    const arg = args[i];

    if (isUndefinedOrNull(arg)) {
      throw new Error(`Assertion Failed: argument at index ${i} is undefined or null`);
    }

    result.push(arg);
  }

  return result;
}

const hasOwnProperty = Object.prototype.hasOwnProperty;

/**
 * @returns whether the provided parameter is an empty JavaScript Object or not.
 */
export function isEmptyObject(obj: unknown): obj is object {
  if (!isObject(obj)) {
    return false;
  }

  for (const key in obj) {
    if (hasOwnProperty.call(obj, key)) {
      return false;
    }
  }

  return true;
}

/**
 * @returns whether the provided parameter is a JavaScript Function or not.
 */
export function isFunction(obj: unknown): obj is Function {
  return typeof obj === 'function';
}

/**
 * @returns whether the provided parameters is are JavaScript Function or not.
 */
export function areFunctions(...objects: unknown[]): boolean {
  return objects.length > 0 && objects.every(isFunction);
}

export type TypeConstraint = string | Function;

export function validateConstraints(
  args: unknown[],
  constraints: Array<TypeConstraint | undefined>,
): void {
  const len = Math.min(args.length, constraints.length);
  for (let i = 0; i < len; i++) {
    validateConstraint(args[i], constraints[i]);
  }
}

export function validateConstraint(
  arg: unknown,
  constraint: TypeConstraint | undefined,
): void {
  if (isString(constraint)) {
    if (typeof arg !== constraint) {
      throw new Error(`argument does not match constraint: typeof ${constraint}`);
    }
  } else if (isFunction(constraint)) {
    try {
      if (arg instanceof constraint) {
        return;
      }
    } catch {
      // ignore
    }
    if (!isUndefinedOrNull(arg) && (arg as any).constructor === constraint) {
      return;
    }
    if (constraint.length === 1 && constraint.call(undefined, arg) === true) {
      return;
    }
    throw new Error(
      `argument does not match one of these constraints: arg instanceof constraint, arg.constructor === constraint, nor constraint(arg) === true`,
    );
  }
}

/**
 * Converts null to undefined, passes all other values through.
 */
export function withNullAsUndefined<T>(x: T | null): T | undefined {
  return x === null ? undefined : x;
}

/**
 * Converts undefined to null, passes all other values through.
 */
export function withUndefinedAsNull<T>(x: T | undefined): T | null {
  return typeof x === 'undefined' ? null : x;
}

type AddFirstParameterToFunction<T, TargetFunctionsReturnType, FirstParameter> =
  T extends (...args: any[]) => TargetFunctionsReturnType
    ? // Function: add param to function
      (firstArg: FirstParameter, ...args: Parameters<T>) => ReturnType<T>
    : // Else: just leave as is
      T;

/**
 * Allows to add a first parameter to functions of a type.
 */
export type AddFirstParameterToFunctions<
  Target,
  TargetFunctionsReturnType,
  FirstParameter,
> = {
  // For every property
  [K in keyof Target]: AddFirstParameterToFunction<
    Target[K],
    TargetFunctionsReturnType,
    FirstParameter
  >;
};

/**
 * Given an object with all optional properties, requires at least one to be defined.
 * i.e. AtLeastOne<MyObject>;
 */
export type AtLeastOne<T, U = { [K in keyof T]: Pick<T, K> }> = Partial<T> & U[keyof U];
